The pigpen cipher (also known as Freemason’s cipher) is the most popular secret writing alphabet in history. It has been used to encrypt gravestone inscriptions, treasure maps, certificates, testaments, mug inscriptions, beer labels and more. Today, I’m going to introduce ten especially interesting uses.

The pigpen cipher (also known as Freemason’s cipher, because it was popular among the Freemasons) is known in several variants. Usually, the cipher alphabet is derived from four tables in the following way:

Using this scheme, the cleartext X MARKS THE SPOT is encrypted as follows:

Sometimes a randomized order of the letters in the four tables is used to make the system more secure. In addition, there are pigpen variants based on only three tables (i.e., the STUV part and the WXYZ part in the figure above are replaced by another 3×3 table with two dots in each field).

The pigpen cipher has been in wide use for centuries. In the following I will give ten examples.

Pigpen gravestone

Some gravestones of Freemasons have pigpen inscriptions. Gravestones of this kind are known to exist in New York City, Manchester, UK, and other places. The following one is located in Newcastle upon Tyne, UK.

The cleartext is A FAITHFUL FRIEND AND LOVING BROTHER.

This pigpen gravestone is one of the lesser-known of its kind. I only know this Freemason website as a source. The site doesn’t say where in Newcastle this gravestone is located. If a reader knows the name of the cemetery or the street address, I would be interested to learn.

Pigpen medal

The following Freemason medal (owned by the Library & Museum of Freemasonry in London) has a pigpen inscription.

As can be seen, a two point pigpen variant is used. See here for a discussion of this medal and its inscription.

NSA pigpen mug

The cleartext reads NATEONAL SECURITY AGENCY. Yes, it contains a typo! This means that the NSA made an encryption mistake, which happens extremely rarely.

Pigpen description af a treasure location

There’s even a text describing the location of a hidden treasure written in pigpen.

It was allegedly created by 17th century pirate Olivier Le Vasseur (also known as “La Buse”). Shortly before he was hanged, he reportedly threw this encrypted note to the people in the audience. The cryptogram has been solved, but the cleartext is quite confusing. Maybe the location of the treasure is hidden in a second tier of encryption. As far as I know, nobody has found the treasure so far.

Pigpen testament of an actress

Diana Dors, an actress known as the Europen Marilyn Monrore, left behind an encrypted message, the headline of which is written in pigpen letters.

The pigpen headline decrypts to LOCATIONS AND NAMES. The rest is an encrypted list of UK locations and names of (non-existing?) persons. The details of this most peculiar story are available here.